A 53-year-old German man formerly diagnosed with HIV has lived for four years without any discernible levels of the virus in his body, after receiving a stem cell transplant. This makes him the fifth confirmed case of a person cured of the virus.

The “Düsseldorf patient,” is about the third person cleared of the virus after a dangerous surgery to entirely replace his bone marrow with HIV-resistant donor stem cells.

The research study leading to this breakthrough was led by Dr Yvonne Bryson, MD, a professor and HIV specialist at the David Geffen School of Medicine at the University of California in Los Angeles. However, Dr Bryson wasn’t involved in the Düsseldorf case.

ART is not a cure but can make HIV undetectable

People with HIV have received antiretroviral therapy (ART) intending to lower the virus to almost undetectable levels. It prevents it from being transmitted to other people. While ART has changed HIV from a terminal illness to a painless chronic condition, reservoirs of the virus can still be stored and replicated by the immune system if ART treatment is stopped.

The few confirmed cases of cures involved people who had very low levels of the virus in their bodies. Even after long periods without taking ART. In the latest case, the Düsseldorf patient halted ART in 2018 and has remained free of the virus since.

This cure involves a stem cell transplant

A man known as the “Berlin patient” marked the first known case of an HIV cure. He lived with HIV in remission for 12 years before dying of cancer. The Berlin patient received a stem cell transplant for leukemia. And the donor cells he received happened to have a mutation that blocks the CCR5 protein from helping HIV overrun healthy cells.

Scientists documented an apparent cure in a second man, called the “London patient,” in 2019. Three years later, scientists announced two more potential cases of a cure, one in New York and one in California.

But it’s unlikely that stem cell transplants would be performed anytime soon for HIV patients without leukemia because of the risks of this procedure. According to this report, this case seems to be a proof of concept. It is not ready for scale-up and relevance to a broader population. However, it brings additional hope for a cure in those who have long-term HIV. And also cancer requiring a stem cell transplant as part of the treatment.